HU KK A OTT

If you want to play this hand tricky like this I don’t think you can fold if an ace comes up.
With the line you took he could have some missed draws that he bluffs 3 streets with and he looks not to tight here or these stats are based on HU only.

Cheers,
SDK1987

Those were his overall stats, and in HU he had been very loose aggressive so he could have had a wide range

I like your line here. Postflop he continues with his whole range and if you just call down you keep it maximum wide and let him bluff your further. If you raised him OTF you would be pot committed and he folds all his cold stone bluffs and continue by going AI only with the hands which have direct equity or drawing hands (which are just about 25% of his cbet range) . Thus, you miss value if you raise OTF you would not be getting extra value from his garbage hands which he is likely to continue bluffing at least one street more.
OTT it is nasty but I think against a loose aggro player you are good enough time with KK to call him down to the end with the pot odds we were given.